The present invention relates generally to identification systems, and more particularly, to an identification system that comprises an RF transponder employing a plurality of transponder chips and a sensor switch for for providing multiple readouts.
The assignee of the present invention manufactures radio frequency (RF) identification systems that include a transponder and a code reader that are coupled by an RF communication link. The transponder comprises a transponder integrated circuit chip whose RF output is coupled to an RF transmit antenna. Data relating to an item is prestored in the transponder chip. The transponder chip is coupled to a sensor that is used to trigger the chip to transmit the stored data. The balance of the identification system includes a code reader that is remotely located from the transponder that is coupled to an RF receive antenna. When the transponder chip is activated, the data is transmitted from the transponder chip to the reader by way of the RF transmit and receive antennas comprising the RF communications link.
Conventional identification systems typically employ a powered sensor coupled to a single transponder chip that is used to process analog information derived from the sensor. The sensor is powered by transponder chip, and is read and interpreted by the transponder chip. This transponder arrangement generates detailed information derived from the sensor, but requires added power and the use of relatively sophisticated and expensive processing techniques in order to read and interpret the sensor data. Furthermore, only one set of data is provided by conventional systems.
Therefore, it is an objective of the present invention to provide for a identification system employing an improved transponder that employs multiple RF transponder chips and sensor switch that provides for transmission of a plurality of distinct sets of data.